Šadauskienė, J., A. Buska, A. Burlingis, R. Bliūdžius, and A. Gailius. “The Effect of Vertical Air Gaps to Thermal Transmittance of Horizontal Thermal Insulating Layer”. Journal of Civil Engineering and Management, vol. 15, no. 3, Sept. 2009, pp. 309-15, https://jcem.vgtu.lt/index.php/JCEM/article/view/6436.